Invoked when request processing has been completed and nothing more
needs to be done. This may be a good place to log some stats and
clean up resources. This is distinct from onEOM() because it is
invoked after the response is fully sent. Once this callback has been
received, downstream_ should be considered invalid.
Invoked when request processing has been completed and nothing more needs to be done. This may be a good place to log some stats and clean up resources. This is distinct from onEOM() because it is invoked after the response is fully sent. Once this callback has been received, downstream_ should be considered invalid.